Referenced Mode Processing
In Referenced Mode, the system operates in a “pseudo closed loop” test scenario where the user plays a specific Reference Audio file (pre-recorded audio test file provided by Frontline) on the Source DUT. The Source DUT negotiates with the Sink DUT to determine the appropriate codec and audio parameters to use and will then process the Reference Audio file accordingly before transmitting the resulting audio via Bluetooth.
The Sink DUT receives the encoded audio, decodes it, and processes it for playback. In parallel, Frontline’s system snoops the over-the-air signal between the Source DUT and Sink DUT and emulates the RF reception and decoding done inside the Sink DUT. Frontline’s Audio Expert System automatically detects that a Reference Audio file is being received and then analyzes the resulting audio for deviations from expected parameters.
The Reference Audio files are specific audio files that exercise the system so that audio impairments can more efficiently and accurately be identified and reported. The Reference Audio files are composed of a series of back-to-back and relatively short duration tones of changing amplitude, frequency, and duration.
The analysis of the received audio results in a series of “Audio Events” being reported by comparing changes in the received audio to expected changes of the Reference Audio, and reporting deviation events when they occur.